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Related papers: PURIFYing real radio interferometric observations

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The sparse layouts of radio interferometers result in an incomplete sampling of the sky in Fourier space which leads to artifacts in the reconstructed images. Cleaning these systematic effects is essential for the scientific use of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-27 Kevin Schmidt , Felix Geyer , Stefan Fröse , Paul-Simon Blomenkamp , Marcus Brüggen , Francesco de Gasperin , Dominik Elsässer , Wolfgang Rhode

This study presents a new image super-resolution (SR) technique based on diffusion inversion, aiming at harnessing the rich image priors encapsulated in large pre-trained diffusion models to improve SR performance. We design a Partial noise…

Computer Vision and Pattern Recognition · Computer Science 2025-03-14 Zongsheng Yue , Kang Liao , Chen Change Loy

We propose a novel method for enhancing phase estimation in the displacement-assisted SU(1,1) (DSU(1,1)) interferometer by incorporating the photon recycling technique, evaluated under single-intensity detection (SID) and homodyne detection…

Quantum Physics · Physics 2025-10-07 Taj Kumar , Aviral Kumar Pandey , Anand Kumar , Devendra Kumar Mishra

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez

Passive radar has key advantages over its active counterpart in terms of cost and stealth. In this paper, we address passive radar imaging problem by interferometric inversion using a spectral estimation method with a priori information…

Signal Processing · Electrical Eng. & Systems 2022-12-06 Samia Kazemi , Bariscan Yonel , Birsen Yazici

We propose a general framework to recover underlying images from noisy phaseless diffraction measurements based on the alternating directional method of multipliers and the plug-and-play technique. The algorithm consists of three-step…

Optimization and Control · Mathematics 2016-11-07 Huibin Chang , Stefano Marchesini

Magnetic Resonance Imaging (MRI) is a powerful technique employed for non-invasive in vivo visualization of internal structures. Sparsity is often deployed to accelerate the signal acquisition or overcome the presence of motion artifacts,…

Image and Video Processing · Electrical Eng. & Systems 2025-05-27 Gianluca Giacchi , Isidoros Iakovidis , Bastien Milani , Micah Murray , Benedetta Franceschiello

The standard imaging algorithm for interferometric radio data, CLEAN, is optimal for point source observations, but suboptimal for diffuse emission. Recently, RESOLVE, a new Bayesian algorithm has been developed, which is ideal for extended…

Instrumentation and Methods for Astrophysics · Physics 2017-02-28 Maksim Greiner , Valentina Vacca , Henrik Junklewitz , Torsten A. Enßlin

Radio interferometer arrays with non-homogeneous element patterns are more difficult to calibrate compared to the more common homogeneous array. In particular, the non-homogeneity of the patterns has significant implications on the…

Instrumentation and Methods for Astrophysics · Physics 2021-05-26 Jake L. Jones , Randall B. Wayth

SKA is a new technology radio-telescope array, about two orders of magnitude more sensitive and rapid in sky surveys than present instruments. It will probe the dark age of the universe, just afer recombination, and during the epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Francoise Combes

Producing ultra-deep high-angular-resolution images with current and next-generation radio interferometers introduces significant computational challenges. In particular, the imaging is so demanding that processing large datasets,…

Instrumentation and Methods for Astrophysics · Physics 2025-01-14 J. M. G. H. J. de Jong , R. J. van Weeren , T. J. Dijkema , J. B. R. Oonk , H. J. A. Röttgering , F. Sweijen

As radio telescopes become sensitive, radio frequency interference (RFI) is more and more serious for interesting signals of radio astronomy. There exist demands for developing an automatic, accurate and efficient RFI mitigation method.…

Instrumentation and Methods for Astrophysics · Physics 2023-12-27 Qingguo Zeng , Xue Chen , Xiangru Li , J. L. Han , Chen Wang , D. J. Zhou , Tao Wang

This paper studies a type of image priors that are constructed implicitly through the alternating direction method of multiplier (ADMM) algorithm, called the algorithm-induced prior. Different from classical image priors which are defined…

Computer Vision and Pattern Recognition · Computer Science 2016-02-03 Stanley H. Chan

Modern interferometric imaging relies on advanced calibration that incorporates direction-dependent effects. Their increasing number of antennas (e.g. in LOFAR, VLA, MeerKAT/SKA) and sensitivity are often tempered with the accuracy of their…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 K. Iheanetu , J. N. Girard , O. Smirnov , K. M. B. Asad , M. de Villiers , K. Thorat , S. Makhathini , R. A. Perley

Intensity interferometry (II) exploits the second-order correlation to acquire the spatial frequency information of an object, which has been used to observe distant stars since 1950s. However, due to unreliability of employed imaging…

Image and Video Processing · Electrical Eng. & Systems 2017-12-08 Wentao Wang , Qi Han , Hui Chen , Yuan Yuan , Zhuo Xu

Photoacoustic (PA) imaging is a biomedical imaging modality capable of acquiring high-contrast images of optical absorption at depths much greater than traditional optical imaging techniques. However, practical instrumentation and geometry…

Computer Vision and Pattern Recognition · Computer Science 2021-06-02 Mengjie Guo , Hengrong Lan , Changchun Yang , Fei Gao

We propose a new technique to obtain super-resolution images with radio interferometer using sparse modeling. In standard radio interferometry, sampling of ($u$, $v$) is quite often incomplete and thus obtaining an image from observed…

Instrumentation and Methods for Astrophysics · Physics 2014-07-10 Mareki Honma , Kazunori Akiyama , Makoto Uemura , Shiro Ikeda

Radio Frequency Interference (RFI) increasingly contaminates the radio astronomy spectrum, often exceeding astronomical signal amplitudes by 50-70 dB. Reliable detection and mitigation are therefore essential for studies of faint transient…

Instrumentation and Methods for Astrophysics · Physics 2026-05-08 Natalia A. Schmid , Sasanka Katreddi , Yechan Kweon

Calibration of radio interferometric observations becomes increasingly difficult towards lower frequencies. Below ~300 MHz, spatially variant refractions and propagation delays of radio waves traveling through the ionosphere cause phase…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 H. T. Intema , S. van der Tol , W. D. Cotton , A. S. Cohen , I. M. van Bemmel , H. J. A. Rottgering

Context. Modern radio astronomical arrays have (or will have) more than one order of magnitude more receivers than classical synthesis arrays, such as the VLA and the WSRT. This makes gain calibration a computationally demanding task.…

Instrumentation and Methods for Astrophysics · Physics 2014-10-09 Stefano Salvini , Stefan J. Wijnholds
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